Conveying disk for heat-treating furnaces



Patented Dec. 9, 1952 CQNVEYING DISK FOR HEAT-TREATING FURNACES WilliamE. Blythe, Birmingham, Mich, assignor to Driver-Harris Company,Harrison, N. J., a corporation of New Jersey Application December 17,1949, Serial No. 133,567

3 Claims. 1

The present invention relates to high temperature heat-treating furnacesof the type in which the material to be treated is conveyed through thefurnace on wheels or disks, and has special reference to the wheels ordisks of such furnaces.

Ihe principal object of the invention is to provide a material-conveyingdisk of the character indicated which may be easily removed andreplaced, and which is capable of withstanding the high heat of thefurnace Without warping or otherwise being injuriously aifected.

Th invention is iliustrated, by way of example, in the accompanyingdrawings, in which:

Figure 1 is a transverse sectional View, partly in elevation, of afurnace having material-conveying disks embodying features of thinvention in their preferred form;

Fig. 2 is a side view, partly in section, of one of the disks attachedto a furnace shaft, the shaft being shown in section;

Fig. 3 is a sectional view, partl in elevation, taken on the line 3-3 ofFig. 2;

Figs. 4, 5 and 6 are sectional views, partly in elevation, takenrespectively on the lines 4--i, E5, and 66 of Fig. 2; and

Fig. 7 is a plan view of a portion of the rim of the disk.

The furnace illustrated in Fig. 1 of the drawings maybe of the type ofthe one described and claimed in my Letters Patent Reissue No. 19,205,dated June 12, 1934; No. 1,992,466, dated February 25, 1935; and No.1,992,467, dated February 26, 1935. This furnace is provided with afurnace chamber having side walls 2, a bottom wall 4, hollow conveyorrolls or shafts 6 extending transversely of the furnace chamber,bearings 8 within the chamber for supporting the shafts,material-conveying disks it carried by the shafts, the disks of theseveral shafts being arranged in staggered relation.

In accordance with the present invention, each disk ii is provided witha hub l2, radially extending spokes Hi, and a rim 1 6.

The hub 52 is made in two longitudinal sections which embrace the shaftwith their opposed longitudinal edges spaced apart to allow forexpansion and contraction.

Th two sections of the hub may be secured to the shaft by means of abolt [8 which extends through alined apertures in the sections andshaft. As shown the bolt is held in place by means of a head It on oneend thereof, and a taper pin 2i} removably secured in an aperture in itsother end. The apertures through which the bolt extends are madeslightly larger in diam- 2 eter than the bolt to allow for expansion andcontraction and to permit the bolt to be easily removed upon removingthe retaining pin 20.

The hub sections may also be removably secured separately to the shaftby means of a bolt 22 which extends through an aperture in each section,and its end which is reduced in diameter is screw-threaded into anaperture in the shaft. The apertures in the hub sections are slightlylarger than the bolts to allow for expansion and contraction and easyremoval of the bolt.

While for convenience both the bolt l8 and the bolts 22 are shown inFig. 2, only one such securing means need be employed.

Three of the six spokes E4 of each disk project from each hub section,there being a central spoke and two spokes spaced from the centralspoke. The spokes are provided with longitudinally extending reinforcingribs 24 on the sides thereof, and the outer ends of the spokes have flatparallel sides and extend into an annular groove 26 on the inner side ofthe rim Hi. The

side walls of the groove 26 are spaced slightly,

away from the sides of the ends of the spokes to allow for expansion andcontraction between these parts. The central spoke of each section isprovided with a laterally enlarged outer end 28. The rim i8 is made intwo sections with the split or opposed ends of the sections spacedslightly apart to allow for expansion and contraction, and are arrangedat an angle of substantially forty-five degrees so as not to interferewith the travel of the material over the disks. The end portions of thewalls of the groove 26 in the sections are provided with inwardlyrojecting lugs or ears 30 which are provided with apertures in alinementwith apertures in the enlarged ends 28 of the central spokes of the twohub sections. The ends of the rim sections are secured to the centralspokes by means of bolts or screws 32 that extend through the aperturesin one wall of the groove 25, and through the apertures in the ends ofthe central spokes, and are threaded into the apertures in the otherwall of the groove 26, there being a slight clearance space providedbetween the outer portion of each screw and the walls of the aperturesto allow for expansion and contraction and for easy removal of thescrews.

With this construction, it will be apparent that the sections of thedisks may be easily detached, and the disks separately removed andreplaced without removing their shafts from the furnace 3 chamber, andthe disks are of simple and strong construction.

Heat-treating furnaces of the type described are heated up to the hightemperature of 1900 degrees F. at which they normally operate. When thusoperated, the rims of the disks heat up considerably faster than thehubs. Conversely when the furnace cools down the rims cool considerablyfaster than the hubs. In the case of disks heretofore in generalcommercial use, this develops very severe thermal stresses which tend towarp the disks, and in some instances causes them to curve to suchextent that the disks on adjacent shafts interfere. It will be apparentthat with my specific construction, the rim and hub and the sectionsthereof are free to expand and contract independently of each other, andit has been found that the tendency of the disks to warp is effectivelyovercome.

As will be evident to those skilled in the art,

my invention permits various modifications without departing from thespirit thereof or the scope of the appended claims.

What I claim is:

l. A conveying disk for a shaft of a heat-treating furnace of the classdescribed, comprising a hub made in two longitudinally extendingsections, a centrally located spoke and spokes spaced circumferentiallytherefrom projecting radially from each hub section, means fordetachably sewith its ends arranged centrally of said centrally locatedspokes, and means for detachably securing the ends of the rim sectionsto said centrally located spokes comprising members extending throughapertures in one of the walls forming said groove and apertures in theends of said spokes and detachably secured in apertures in the otherwall of said groove, the sections of said rim, said rim sections and theends of said spokes, the sections of the hub, and said securing meansand connected parts, having clearance spaces between their adjacentsurface portion to allow for expansion and contraction of the sectionsof said rim and the sections of said hub independently of each other.

2. A conveying disk for a shaft of a heat-treating furnace of the classdescribed, comprising a hub made in two longitudinal sections, acentrally located spoke and spokes spaced circumferentially therefromprojecting from each hub section, means for detachably securing the hubsections about said shaft, a rim having an annular groove on its innerside for receiving the ends of the spokes of the two hub sections, saidrim being made in two transverse sections with its ends arrangedcentrally of said centrally located spokes, and means for detachablysecuring the ends of the rim sections to the ends of said centrallylocated spokes, the sections of said rim, said rim sections and the endsof said spokes, the sections of the hub, and said securing means andconnected parts, having clearance spaces between their adjacent surfaceportions to allow for expansion and contraction of the sections of saidrim and the sections of said hub independently of each other.

3. A conveying disk for a shaft of a heat-treating furnace of the classdescribed comprising a hub made in two longitudinally extendingsections, a plurality of spokes projecting radially from each hubsection, the spokes of the two hub sections being diametrically inalinement respectively, and the several spokes being spaced apartcircumferentially, a rim having an annular groove in its inner side forreceiving the ends of the spokes of the two hub sections, said rim beingmade in two transverse sections with its ends arranged centrally of theends of two of the diametrically alined spokes of the two hub sections,and means for detachably securing the ends of the rim sections to theends of said last mentioned diametrically alined spokes, the sections ofsaid rim, said rim sections and the ends of said spokes, the sections ofthe hub, and said securing means and connected parts having clearancespaces between their adjacent surface portions to allow for expansionand contraction of the sections of said rim and the sections of said hubindependently of each other.

WILLIAM E. BLYTHE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 288,522 Walker Nov. 13, 1883393,041 Thorp Nov. 20, 1888 1,861,489 Brooke et al June 7, 19321,923,036 Knopf Aug. 15, 1933 1,923,772 Carpenter Aug. 22, 1933

